The present invention relates to a method and an arrangement for transmitting and extracting a timing signal, and finds particular application in a system for parallel data transmission by the use of a plurality of carriers.
Parallel data transmission over multiple carriers is attracting particular interest in recent years, as it permits transmission of a large amount of data over a transmission line limited in bandwidth, such as a telephone line. One example of a system for such parallel data transmission is described in the U.S. Pat. No. 4,438,511. In the prior art, the transmission and extraction of a timing signal for such a system is achieved by transmitting one of a plurality of carriers as a pilot signal for the timing signal on the transmitting side and extracting the pilot signal on the receiving side. However, such a method for transmitting and extracting a timing signal has the disadvantage that, because one of the carriers in a transmission band, which could otherwise be used for data transmission, is used as a pilot signal, the quantity of transmissible information is correspondingly reduced.